Anki-esque Stats System

[rajlego]

Built in SM stat graphs can already give you a lot of details but I think there are 3 weaknesses:

1. difficult/complicated to navigate and understand for beginners
2. SM graphs don't really give you a good sense of long-term progress. Compare the two below graphs:
   
   
   The latter conveys more information and from it, I can take away that between 20 to 40 months ago many cards were added which then became mature and lowered overall burden. It's much harder to get anything meaningful from the SM graphs.
3. It is really hard to compare SM stats to Anki stats. If I tell someone that SM has a better algorithm and they doubt it, I don't have anything I can really show them that they could effectively compare with Anki. I know the data is all there but I don't have a good way to show it to them.

Example of Full Anki Stats: